JP5268698B2 - Bioreactor fluidized bed biological treatment equipment - Google Patents

Description

  The present invention relates to a bioreactor fluidized bed biological treatment apparatus for biologically treating wastewater containing organic matter.

  Conventionally, as a bioreactor fluidized bed biological treatment apparatus, one having a function of performing biological treatment of wastewater in a predetermined reaction tank equipped with a carrier on which microorganisms are immobilized has been widely proposed (for example, Patent Documents). 1 to 4).

In FIG. 8, the schematic block diagram of the principal part of the conventional bioreactor fluidized bed type biological treatment apparatus is shown.
The bioreactor fluidized bed type biological treatment apparatus shown in the main part of FIG. 8 is a bioreactor tank 100 for biologically treating wastewater subjected to primary treatment such as removal of foreign substances such as dust and agglomeration, and the bioreactor. A circulation tank 101 that performs drainage circulation between the tank 100 and predetermined pipes 102 and 104 is provided.
The bioreactor tank 100 includes a predetermined carrier (pulverized activated carbon particles in which predetermined microorganisms are supported on the surface and inside pores) inside.
The carrier flows in a floating state in the bioreactor tank.

Water is contained in the circulation tank 101, and air is introduced from the blower 105. In the water in the circulation tank 101, oxygen is dissolved to near saturation.
The oxygen-dissolved water is introduced from the lower part into the bioreactor tank 100 from the circulation tank 101 via the pipe 104, and returns to the circulation tank 101 via the pipe 102 after biological treatment.

In this way, the waste water after biological treatment enters the circulation tank 101 from the pipe 102 and further becomes oxygen-dissolved water that goes to the bioreactor tank 100 through the pipe 104, but the overflow is recovered from the pipe 103 as treated water. The
The collected treated water is discharged to a river or the like as it is under the condition that a predetermined water quality standard is cleared, or used as industrial water after a predetermined treatment such as sand filtration.

By the way, sludge is generated with biological treatment in the bioreactor tank 100, and this sludge adheres to the carrier. However, the carrier with sludge has a low specific gravity, and may eventually flow out from the upper part of the bioreactor tank 100. There is.
When the amount of the carrier in the bioreactor tank 100 is reduced, the biological treatment capacity is lowered, so that periodic sludge removal work is required.

In order to remove sludge from the bioreactor tank 100, first, the circulation of the waste water in the bioreactor tank 100 is stopped, and the upper supernatant water is extracted using the pump 108 as shown in FIG.
Next, as shown in FIG. 9, the worker 110 puts a predetermined nozzle 111 into the carrier and sludge deposit 112 in the bioreactor tank 100 from the upper part of the reaction tank 100, and supplies high-pressure air from the nozzle port. Pour and air agitate to remove sludge from the carrier.
By allowing the carrier to stand for a predetermined time after air stirring, the carrier having a high specific gravity settles and becomes a lower layer, and the sludge becomes an upper layer and both are separated.
Next, the sludge is sucked by the pump 108 shown in FIG. 8 and discharged out of the bioreactor tank 100.
Thereafter, the bioreactor tank 100 is filled with wastewater to be treated, and the above-described biological treatment is resumed.

Japanese Patent No. 3350424 JP 2000-176462 A JP 2004-73986 A JP 2005-7275 A

However, in the above-described conventional technology, it is necessary to perform the separation of the sludge and the carrier and the removal of the sludge with the drainage circulation of the bioreactor tank 100 and the like stopped, and the purification treatment of the wastewater is interrupted. The Moreover, since it takes time for the carrier to settle after separating the sludge and the carrier, there is a problem that the overall work efficiency is extremely poor.
Furthermore, since the operator has to perform the stirring work of the carrier and the sludge, there is a problem that the total cost of the wastewater treatment is increased.

  Therefore, in the present invention, it is possible to automatically perform the separation of sludge and the carrier, the discharge of the sludge, and the recovery of the carrier without stopping the drainage circulation, thereby dramatically improving the efficiency of the wastewater treatment work. Provided is a bioreactor fluidized bed biological treatment apparatus.

The invention of claim 1 is a bioreactor fluidized bed biological treatment apparatus for purifying waste water, comprising a bioreactor tank comprising a carrier on which microorganisms are supported, and the bioreactor tank, with stirring means A sludge stripping mechanism that is a centrifugal pump, a sludge stripping mechanism that communicates with the sludge stripping mechanism and the bioreactor tank, contains sludge and a carrier, and performs sedimentation separation of the carrier; and returns the carrier to the bioreactor tank the carrier returning means and sludge possess the sludge discharge mechanism having a sludge delivery means for delivering out of the sludge separation tank, a, in the sludge discharge mechanism, the carrier separated by sedimentation and the sludge in the sludge separation tank, While sending the separated sludge out of the sludge separation tank, the amount of deposition of the carrier is detected and transferred to the bioreactor tank by the carrier return means. Controlling the timing of the carrier return, provides a bioreactor fluidized bed biological treatment device.

In the invention of claim 2, the sludge discharge mechanism includes carrier detection means for detecting the interface of the carrier in the sludge separation tank, and the carrier detection means is a tuning fork type sensor. A bioreactor fluidized bed biological treatment device as described is provided.

  According to the bioreactor fluidized bed biological treatment apparatus of the present invention, the separation of sludge and the carrier, the sludge discharge, and the carrier recovery are automated without interrupting the liquid circulation of the bioreactor tank and the wastewater treatment work. It is possible to provide a bioreactor fluidized-bed biological treatment apparatus that can dramatically improve the efficiency of wastewater treatment work and has an extremely high carrier recovery rate.

The schematic block diagram of an example of the bioreactor fluidized bed type biological treatment apparatus in this embodiment is shown. The schematic block diagram of the principal part of an example of the bioreactor fluidized bed type biological treatment apparatus in this embodiment is shown. The schematic of the process (before interface detection) which detects a support | carrier interface using an ultrasonic vibrometer (tuning fork type sensor) is shown. The schematic of the process (after interface detection) which detects a support | carrier interface using an ultrasonic vibrometer (tuning fork type sensor) is shown. (A) The state of the support | carrier before a sludge peeling process is shown. (B) The state of the carrier after the sludge stripping step is shown. (A) The state of the support | carrier before a sludge peeling process is shown. (B) The state of the carrier after the sludge stripping step is shown. (A) The state of the support | carrier before a sludge peeling process is shown. (B) The state of the carrier after the sludge stripping step is shown. The schematic block diagram of the principal part of the conventional bioreactor fluidized bed type biological treatment apparatus is shown. The schematic of the conventional sludge removal work process is shown.

Hereinafter, modes for carrying out the present invention (hereinafter referred to as the present embodiment) will be described with reference to the drawings.
In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the positional relationship such as up, down, left, and right is based on the positional relationship shown in the drawings unless otherwise specified, and the dimensional ratio in the drawing is not limited to the illustrated ratio.

A bioreactor fluidized bed biological treatment apparatus and a wastewater treatment process performed using the bioreactor fluidized bed biological treatment apparatus in the present embodiment will be described.
In the present specification, the term “bioreactor fluidized bed biological treatment apparatus” refers to biodegradation in a bioreactor tank by microorganisms in which organic substances contained in wastewater are supported on a carrier, and then the carrier and An apparatus that obtains clear treated water while automatically performing the process of separating sludge, discharging sludge, and recovering the carrier.

[Bioreactor fluidized bed biological treatment equipment]
FIG. 1 shows a bioreactor fluidized bed biological treatment apparatus in which a step of separating sludge and a carrier generated by biological treatment, a step of discharging sludge out of the system, and a step of collecting the carrier are automated. The schematic block diagram of an example is shown.
This bioreactor fluidized bed biological treatment apparatus includes a drain tank 1, a reaction / coagulation tank 2, a coagulation sedimentation tank 3, a bioreactor tank 4, a circulation tank 5, a sludge stripping mechanism 6, a blower 7, a sludge discharge mechanism 8, and a sludge. The tank 9 is configured.

The drainage tank 1 contains a stock solution of drainage.
The stock solution of the wastewater is sent to the reaction / flocculation tank 2 through the pipe H1, and an inorganic flocculant and a polymer flocculant are added to adjust the pH, and the suspension of the suspended suspended matter in the wastewater is performed.

Next, the waste water is sent to the coagulation sedimentation tank 3 through the pipe H2, and the aggregate is concentrated and settled. The sediment is sent to the sludge tank 9, and is carried out as a solid cake through a filter press process.
The waste water (primary treatment water) after passing through the coagulation sedimentation tank 3 is sent to the bioreactor tank 4 through the pipe H3 and subjected to biological treatment (secondary treatment). In addition, the waste water generated by the filter press process is also sent to the bioreactor tank 4 through the pipe H4, and biological treatment is performed.

In FIG. 2, the schematic block diagram of the principal part of an example of the bioreactor fluidized bed type biological treatment apparatus in this embodiment is shown.
The bioreactor tank 4 includes a carrier (not shown) on which microorganisms are supported. As the carrier, for example, pulverized activated carbon particles having aerobic microorganisms attached to the surface and anaerobic microorganisms attached to the inside thereof can be used. By using such a carrier, activated carbon is anaerobically treated with microorganisms adhering to the surface of the activated carbon, and anaerobic treatment with microorganisms adhering to the inside while contacting the wastewater, Decomposition is performed efficiently.
By circulating the waste water from the lower part of the bioreactor tank 4 at a low flow rate, the carrier can be fluidized and classified naturally, and microorganisms are clogged at the bottom of the bioreactor tank 4. Can be effectively avoided.
Furthermore, the carrier-adhered microorganisms grown in the organic matter high concentration region at the bottom of the tank float on the top of the tank by natural classification and reach the organic matter low concentration region, thereby promoting self-digestion and suppressing the generation of excess sludge. .

The circulation tank 5 contains water, and air is introduced by a blower 7 connected to the circulation tank 5.
For this reason, oxygen is dissolved in the water in the circulation tank 5 to near saturation.
The wastewater in which oxygen dissolved through the circulation tank 5 is dissolved is introduced from the bottom of the tank into the bioreactor tank 4 through the pipe H5 from the circulation tank 5 by the operation of the pump P1. Further, drainage is introduced from the upper part of the bioreactor tank 4 into the circulation tank 5 through the pipe H6.
As a result, the waste water is circulated between the bioreactor tank 4 and the circulation tank 5.

  In the bioreactor fluidized bed biological treatment apparatus of this embodiment, the bioreactor tank 4 and the circulation tank 5 are provided independently, and aeration is not performed in the bioreactor tank 4. Inside 4 is a calm environment without air agitation, where a wide variety of microorganisms can inhabit, the food chain is activated, and the generation of excess sludge is suppressed.

The sludge peeling mechanism 6 communicates with the bioreactor tank 4 through a pipe H7.
The sludge peeling mechanism 6 includes a predetermined tank for storing the sludge and the carrier after the biological treatment by the bioreactor tank 4 and a stirring means having a function of sucking and stirring the sludge and the carrier. The stirring means is not particularly limited as long as it has a function of separating the mixture of sludge and the carrier with a shearing force without breaking the carrier. For example, a stirring blade can be applied.
A specific example of the sludge peeling mechanism 6 is a centrifugal pump.

The sludge discharge mechanism 8 communicates with the sludge stripping mechanism 6 via the pipe H8, and communicates with the bioreactor tank 4 via the pipe H9.
The sludge discharge mechanism 8 includes, for example, a cylindrical sludge separation tank having a diameter of 500 mm. In this sludge separation tank, the sludge and the carrier fed from the sludge separation mechanism 6 through the pipe H8 are stored, and sedimentation separation is performed. Made.
The sludge discharge mechanism 8 is a carrier return means (not shown) for returning the carrier to the bioreactor tank 4 through the pipe H9, for example, a valve, and a sludge delivery means (not shown) for sending the sludge outside the sludge separation tank through a predetermined pipe. ) For example, a valve is provided.

  The sludge discharge mechanism 8 preferably includes a carrier detection means 10 having a function of detecting the interface of the carrier that has settled in the sludge separation tank. By detecting the interface of the carrier in the sludge separation tank, the amount of carrier deposition can be known, the control of the carrier return timing to the bioreactor tank 4 by the carrier return means is facilitated, and the working efficiency is improved.

Examples of the carrier detection means 10 include an ultrasonic vibrometer, for example, a tuning fork type sensor.
The process of detecting the carrier interface using the tuning fork type sensor will be described with reference to FIGS.
First, the tuning fork type sensor is arranged in advance at a desired position where the interface reaches the tip of the vibrating part due to the deposition of the carrier.
In a state where the carrier is not sufficiently deposited, that is, in a state where the carrier interface does not reach the tip position of the vibration part of the tuning fork type sensor, the vibration of the vibration part is not hindered, as shown in FIG. A waveform is detected.
On the other hand, when the carrier is sufficiently deposited, the carrier interface reaches a height exceeding the tip position of the vibration part of the tuning fork type sensor and the vibration is hindered, so that the vibration waveform is detected as shown in FIG. It will not be done.
Thus, the carrier deposition amount can be detected by detecting the vibration waveform of the tuning fork type sensor.

In the bioreactor fluidized bed biological treatment apparatus in this embodiment, the sludge and the carrier are sucked by the sludge peeling mechanism 6, introduced into the sludge discharge mechanism 8, the detection of the carrier interface and the sludge discharge in the sludge discharge mechanism 8 are automatically performed. It has a mechanism to be performed.
For example, when the sludge generated in the bioreactor tank 4 reaches a predetermined amount, a predetermined drive signal for operating the sludge stripping mechanism 6 is transmitted, and the sludge stirred and separated in the sludge stripping mechanism 6 and The carrier is introduced into the sludge discharging mechanism 8, and the carrier detecting means 10 is operated in the sludge discharging mechanism 8, and a predetermined operation signal for operating the carrier returning means and the sludge sending means is transmitted according to the detection result. It can be assumed that

[Wastewater treatment process]
Next, the waste water treatment process using the bioreactor fluidized bed biological treatment apparatus in the present embodiment will be described with reference to the schematic view of the main part of the apparatus in FIG.
In the following, the steps after the secondary treatment for the waste water (primary treated water) that has undergone the treatment in the reaction / coagulation tank 2 and the coagulation sedimentation tank 3 shown in FIG. 1 will be mainly described.

  The primary treated water is sent to the bioreactor tank 4 through the pipe H5, where biodegradation by the microorganisms supported on the carrier, that is, BOD component removal, nitrogen removal, phosphorus removal, sludge self-digestion and predation, sludge Flocking (bioaggregation) is performed. In the bioreactor tank 4, the form and operating conditions can be appropriately selected according to the target processing target. For example, when the main purpose is to remove the BOD component, In the case where the purpose is to remove nitrogen and phosphorus, it is possible to use operating conditions mainly including an anaerobic process.

In parallel with the biodegradation, wastewater is circulated in the bioreactor tank 4 and the circulation tank 5 through the pipes H5 and H6.
In the circulation tank 5, oxygen is dissolved in the wastewater to near saturation by the air introduced from the blower 7, and this oxygen-dissolved water is introduced from the lower part of the bioreactor tank 4 through the pipe H <b> 5. From the upper part of the bioreactor tank 4, waste water is sent to the circulation tank 5 through the pipe H6. Such drainage circulation activates microorganisms and promotes purification treatment.

As described above, the wastewater after the biological treatment enters the circulation tank 5 through the pipe H6 and further becomes oxygen-dissolved water that goes to the bioreactor tank 4 through the pipe H5, but the overflow is recovered from the pipe H11 as treated water.
The collected treated water is discharged to a river or the like as it is under the condition that a predetermined water quality standard is cleared, or used as industrial water after a predetermined treatment such as sand filtration.

  The sludge produced by biological treatment in the bioreactor tank 4 and the carrier on which the sludge is adhered are sucked by the sludge peeling mechanism 6 such as a centrifugal pump through the pipe H7, and further the stirring means of the sludge peeling mechanism 6 such as stirring Stir with feathers. The sludge is peeled off from the carrier by the shearing force generated by this suction and stirring.

Subsequently, the sludge and the carrier are sent to the sludge discharge mechanism 8 through the pipe H8.
Since the specific gravity of sludge is lighter than that of the carrier, the carrier settles down in the sludge separation tank of the sludge discharge mechanism 8 and the sludge and the carrier are separated.
At this time, the interface of the carrier is detected by an ultrasonic vibrometer as the carrier detecting means 10, for example, a tuning fork type sensor, and when the carrier is deposited in a desired amount, the carrier returned to the bottom of the sludge discharging mechanism 8 is returned. The carrier is returned to the bioreactor tank 4 through the pipe H9 by opening a valve, for example. Moreover, sludge is discharged out of the system through the pipe H10 by opening a sludge return means provided at a predetermined position on the wall of the sludge discharge mechanism 8, for example, a valve.
The sludge discharged out of the system is treated again in the reaction / coagulation tank 2 and the coagulation sedimentation tank 3 shown in FIG.

The bioreactor fluidized bed biological treatment apparatus in the present embodiment shown in FIGS. 1 and 2 was used to separate the sludge from the carrier by the sludge peeling mechanism 6 and to separate the sludge and the carrier from the sludge discharge mechanism 8. .
Before the sludge stripping process, that is, the state of the carrier at the position of the pipe H7 introduced from the bioreactor tank 4 to the sludge stripping mechanism 6, and after the sludge stripping process, that is, the pipe H9 returned to the bioreactor tank 4 from the sludge discharge mechanism 8 The state of the carrier at the position of was observed.
The sludge peeling mechanism 6 is a self-priming pump model No. BVR400S manufactured by Shin Meiwa Kogyo Co., Ltd., with a power of 0.4 kW, a stirring blade rotation speed of 3000 rotations / minute, and a throughput of 0.1 m ³ / minute. And sludge stripping.
As the carrier detection means 10, a tuning fork type level meter model number FTM51 manufactured by Endless Hauser was used.
Before the sludge peeling step, as shown in FIGS. 5 (a), 6 (a), and 7 (a), sludge was adhered around the carrier, but after the sludge peeling step, FIG. As shown in (b), FIG. 6 (b), and FIG. 7 (b), the carrier from which sludge was reliably removed was recovered.
In addition, the decrease in the diameter of the carrier due to the sludge stripping process was slight, and it was confirmed that it can be used repeatedly many times without causing any practical problems.

  The bioreactor fluidized bed biological treatment device of the present invention can be used industrially as a device for performing public wastewater such as sewage and human waste, industrial wastewater such as food and chemicals, and environmental purification such as lakes and rivers. is there. The treated water can be used not only for discharging into rivers and the like but also as reclaimed water for vehicle washing.

DESCRIPTION OF SYMBOLS 1 Drain tank 2 Reaction / coagulation tank 3 Coagulation sedimentation tank 4 Bioreactor tank 5 Circulation tank 6 Sludge peeling mechanism 7 Blower 8 Sludge discharge mechanism 9 Sludge tank 10 Carrier detection means 100 Bioreactor tank 101 Circulation tank 102, 104 Piping 105 Blower 108 Pump 110 Worker 111 Nozzle 112 Deposit H1, H2, H3, H4, H5, H6, H7, H8, H9 Piping P1 Pump

Claims (2)

A bioreactor fluidized bed biological treatment device for purifying wastewater,
A bioreactor tank comprising a carrier carrying microorganisms;
A sludge stripping mechanism that is in communication with the bioreactor tank and is a centrifugal pump equipped with stirring means;
A sludge separation tank that communicates with the sludge peeling mechanism and the bioreactor tank, and contains and separates sludge and a carrier, a carrier return means for returning the carrier to the bioreactor tank, and a sludge delivery means for sending the sludge out of the sludge separation tank. possess and sludge discharge mechanism comprising, a,
In the sludge discharge mechanism, the carrier is settled and separated from the sludge in the sludge separation tank, and the deposited amount of the carrier is detected while the separated sludge is sent out of the sludge separation tank, and the carrier is returned. Controlling the timing of carrier return to the bioreactor tank by means,
Bioreactor fluidized bed biological treatment equipment. 2. The bioreactor fluidized bed organism according to claim 1, wherein the sludge discharge mechanism includes carrier detection means for detecting the interface of the carrier in the sludge separation tank, and the carrier detection means is a tuning fork type sensor. Processing equipment.